Manufacture of anti-halation or filter layers



Aug. 11, 1936. w. SCHNEIDER 2,050,588

MANUFACTURE OF ANTIHALATION OR FILTER LAYERS Filed Jan. l5, 1952 Sgo/conf /n venfor Patented Aug. 11, 1936 UNITED STATES MANUFACTURE OF ANTI-HALATION OR FILTER LAYERS Wilhelm Schneider, Dessau in Anhalt, Germany,

assigner to Agfa Ansco Corporation, Binghamton, N. Y., a corporation of New York Application January 15, 1932, Serial No. 586,966` In Germany January 21, 1931 14 Claims.

My present invention relates to anti-halation or filter layers for photographic materials.

One of its objects is to provide a method for producing anti-halation layers containing in uniform distribution an azo-dye which is insoluble In water. Another object is photographic materials provided with these anti-halaton layers. Further .objects will be seen from the detailed specification following hereafter. Reference is made to the accompanying drawing in 'which Figs. 1 to 3 show lms or plates in accordance with the present invention in cross-section. In these figures I is the support, 2 is the emulsion layer. In Fig. 1 the lm is provided with a lter layer 3 and in Figs. 2 and 3 the film is provided with an anti-halation layer 4.

I have found that anti-halation layers which do not bleed out in aqueous solutions and in the usual photographic baths and which can be decolorized in a simple manner may be obtained by developing the dye in a solution of a binding agent from its components and producing the layer from this mass. As water insoluble azo dyes which enter into consideration comprising monoand poly-azo-dyes, I enumerate the coupling products of, for instance, aniline, naphthylamine, benzidine, diaminocarbazole, diaminodiphenylene oxide, and the substitution products thereof with the coupling components, for instance, phenols, naphthols and the substitution products thereof. As binding agents for my new anti-halation layer suitable colloids may be used. for instance, gelatine, the calcium salt of polyglycuronic acid and caseine.

The solution of the binding agent is mixed with the coupling component while adding the required amount of alkali, for instance, sodium hydroxide or sodium carbonate, whereupon the diazo-component is added to this mixture while stirring. After having become solid the mass is reduced to small pieces, for instance, cut in strips, and washed until its reaction has become neutral.

From the resulting product the casting solution sodium carbonate.

ing to the reversal method a special bath for removing the coloration of the anti-halation layer can, therefore, be dispensed with. When using the usual negative developing process, after the developing and fixing operation the negative may 5 be treated with an oxidizing bath, for instance, an aqueous solution of 2 grams of potassium permanganate and cc. of sulfuric acid per liter, which bath contains a halide, whereupon the produced silver-halide picture is transformed into I0 a stable silver picture by means of a second exposure and a subsequent reduction by means of a developer or a suitableagent, fort instance hydrosulte.

The following examples illustrate the invenl5 tion:

Example 1.--A solution of '70 parts by weight of gelatine in 800 parts by Weight of water is cooled to 25 C. and mixedwith 100 parts by weight of a molal solution of sodium betanaphtholate and 3 parts by weight of anhydrous Then 100 parts by weight of molal diazo solution of alphanaphthylamine are slowly introduced,-while stirring. The solution immediately becomes intensely red. It is caused to solidify, cut into small pieces and washed with water. After it has been molten, it is utilized in the usual manner for bottom coatings for the emulsion layer or for coating the surface of the emulsion layer or, if required, also the back layer of the support.

Example 2.--A violet colouration is obtained by using in Example l instead of the diazo solution of alphanaphthylamine 100 parts by weight of a- 1/20 molal diaz@ so1ution of dianisidine.. 35

Example 3.-A solution of to 100 parts by Weight of gelatine in 800 parts by weight of water is mixed with parts by weight of T15 molal solution of sodium -naphtholate and 3 parts by weight of sodium carbonate. To this mixture kept at about 25 C. there are added 100 parts by weight of a 1/20 molal diazo solution of benzidine. The solution becomes immediately dark red. The further working up of the mass is as described in Example 1.

Example 4.-When replacing in Example 3 the 116 molal solution of sodium -naphtholate by a 116 molal solution of 1.7-aminophenol andthe l/zo diazo solution of benzidine by a l/20 diazo` solution of dianisidine a greenish blue mass is obtained which yields layer having a nearly black appearance when being about 5 to 6 a thickf Example 5.-A fuchsine-red solution of gelatine is obtainable by using equal parts of a 55 molal solution of sodium p-naphtholate-and of a 1/20 molal diazo solution of toluidine.

Example 6.-A blue solution of gelatine with a .cast to red is obtainable by using equal parts of a 116 molal solution of sodium -naphtholate and a 1/20 molal diazo solution of dianisidine. My invention is not limited to the foregoing examples nor to the specic details given therein and I contemplate as included within my invenlion all such modications and equivalents as fall within the scope of the appended claims.

The term anti-halation layer as used in the specification and the claims is to include antihalation layers and lter layers.

What I claim is 1. A method of producing anti-halation layers which comprises mixing a solution of a binding agent with a. coupling component of an azo dye of the group consisting of monoand polyazo dyes and alkali, adding to this mixture a diazo component, while stirring, reducing the mass after it has become solid to small pieces, washing the pieces until their reaction has become neutral and preparing the anti-halation layers from this product.

2. A method of producing anti-halation layers which comprises mixing a solution of 70 parts by weight of gelatine in 800 partsby weight of water with 100 parts by weight of 116 molal solution of 1.7-aminonaphthol, and 3 parts by weight of anhydrous sodium carbonate cooling the mixture to about 25 C., adding slowly while stirring 100 parts by-weight of a 1/20 molal diazo solution of dianisidine, reducing the mass after it has become solid to small pieces, washing the pieces V until their reaction has become neutral, and preparing the layers from this product.

3. A method of producing anti-halation layers which comprises mixing a solution of- '70 parts by weight of gelatine in 800 parts by weight of Water with 100 parts by weight of a 11s molal solution of sodium -naphtholate, and 3 parts by weight of anhydrous sodium carbonate, cooling the mixture to about 25C., adding slowly while stirring 100 parts by weight of a 116 molal diazo solution of a-naphthylamin, reducing the mass after it has become solid to small pieces, washing the pieces until their reaction has become neutral, and preparing the layerslfrom this product.

4. A method of producing anti-halation layers which comprises mixing a solution of parts by weight oir gelatine in 800 parts by weight of water with parts by weight of a 116 molal solution of sodium -naphtholate, and 3 parts by weight of anhydrous sodium carbonate cooling the mixture to about 25 C., adding slowly while stirring'lOO parts by weight of a 1/m molal diazo solution of benzidine, reducing the mass after it has become solid to small pieces, washing the pieces until their reaction has become neutral, and preparing the layers from this product.

5. A method oi' producing anti-halation layers which comprises mixing a solution of gelatine with a coupling component of an azo dye of the group consisting of monoand polyazo dyes and alkali, adding to this mixture a diazo component, while stirring, reducing the mass after it has become solid to small pieces, washing the pieces until their reaction has become'neutral and preparing the anti-halation layers from this product.

6. A photographic material which comprises a support, a light sensitive silver-halide emulsion and an anti-halation layer comprising a binding agent and an azo dye, said azo dye being insoluble in water. I

7. A photographic material which comprises a support, a light sensitive silver-halide emulsion and an anti-halation layer comprising a binding agent and an azo dye. said azo dye being insoluble in water, but soluble in the oxidizing reversal baths.

8. A photographic material which comprises a support, a light sensitive silver-halide emulsion. and an anti-halation layer comprising a. binding agent and an azo dye, said azo dye being insoluble in water, but soluble in a solution of potassium permanganate and sulfuric acid.

9. A photographic material which comprises a support, a light-sensitive silver halide emulsion and an anti-halation layer containing the azo dye from 1.7-amino-naphthol and di-anisidine.

10. A photographic material which comprises a support, a light-sensitive silver halide emulsion and an anti-halaton layer containing the azodye from sodium -naphtholate and a-naphthylamine.

11. A photographic material which comprises a support, a light-sensitive silver halide emulsion and an anti-halation layer containing the azo dye from sodium -naphtholate and benzidine.

12. A photographic material which comprises a support, a light sensitive silver halide emulsion and an anti-halation layer comprising gelatin containing an azo dye insoluble in water.

13. A photographic material which comprises a support, a light sensitive silver halide emulsion and an anti-halation layer comprising gelatin containing an azo dye insoluble in water but soluble in oxidizing reversal baths.

14. A photographic material which comprises a support, a light sensitive silver halide emulsion and an anti-halaton layer comprising gelatin containing an azo dye insoluble in water but soluble in a solution of potassium permanganate and sulfuric acid.

WILHELM SCHNEIDER. 

